Eu-activated fluorochlorozirconate glass-ceramic scintillators

Abstract

Rare-earth-doped fluorochlorozirconate (FCZ) glass-ceramic materials have been developed as scintillators and their properties investigated as a function of dopant level. The paper presents the relative scintillation efficiency in comparison to single-crystal cadmium tungstate, the scintillation intensity as a function of x-ray intensity and x-ray energy, and the spatial resolution (modulation transfer function). Images obtained with the FCZ glass-ceramic scintillator and with cadmium tungstate are also presented. Comparison shows that the image quality obtained using the glass ceramic is close to that from cadmium tungstate. Therefore, the glass-ceramic scintillator could be used as an alternative material for image formation resulting from scintillation. Other inorganic scintillators such as single crystals or polycrystalline films have limitations in resolution or size, but the transparent glass-ceramic can be scaled to any shape or size with excellent resolution.

Europium-doped barium halide scintillators for x-ray and γ-ray detections

“…The scintillation decay components are collected in the last column of Table III. The decay components for Eu-doped BaCl 2 and BaBr 2 are much faster than those observed for the corresponding undoped sample, whereas both undoped and Eu-doped BaI 2 show about the same temporal behavior. The emission in BaI 2 is dominated by the 530 nm band, and its decay can be fitted by assuming two different components.…”

“…1, 2 In contrast to common single-crystal scintillators, glass ceramics can be manufactured easily in any size and shape. The scintillation in these glass ceramics is mainly caused by the 5d-4f transition of europium͑II͒ incorporated in barium chloride nanocrystals that are formed in the glass matrix upon appropriate thermal processing.…”

Eu oxidation state in fluorozirconate-based glass ceramics

“…1,2 The new materials are derived from a standard ZBLAN formulation. ZBLAN is a fluoride glass, made from zirconium, barium, lanthanum, aluminum, and sodium, as the name suggests.…”

“…This enabled precipitation of barium chloride nanocrystals within the glass upon appropriate annealing. Depending on the structural phase of the barium chloride, the glass-ceramic material can act either as a scintillator ͑able to convert ionizing radiation to visible light͒ 1 or as a storage phosphor ͑able to convert the radiation into stable electron-hole pairs, which can be released at a later time with a scanning laser beam͒. 2 In both applications, Eu is added to the glass for optical activation showing an intense luminescence in the blue spectral region upon excitation with ultraviolet light or x rays.…”

“…However, photoluminescence ͑PL͒ and x-ray excited luminescence measurements 1,6 have shown that there is always a significant amount of Eu 3+ in the glass which reduces the performance of these systems as both scintillators and storage phosphors. Specifically, in Ref.…”